While in the Marston hide with Steve N we had a number of Phylloscopus Warblers around us and I was pretty sure there were both Chiffchaff and Willow Warbler present at the time but none were singing. After looking more carefully at a number of photos I am no longer sure which is which of these. The trouble is that the very strong backlighting to some made all legs look pale. In addition it is not really possible to determine wing length from the photos as the angle at which they were taken varies so much. These are from three different birds:
I suspect they are all chiffys but need confirmation.
Also had a Goldcrest around the hide as well: